Carotid artery aneurysm simulating pituitary adenoma

We describe a case of a giant carotid artery aneurysm presenting as an intrasellar mass with suprasellar extension, with radiographic and endocrinologic findings suggestive of pituitary tumor. This case emphasizes that elevated prolactin is not specific for prolactinoma. This case also supports consideration of angiography before proceeding with transsphenoidal surgery for presumed pituitary adenoma.